Newington, Conn.-based Shelco offers the most economical, high efficiency pleated elements available. For your most critical throughput, the MI-Series is the best solution to filtration problems. The cartridge is made of pleated polypropylene or polyester media and has verified efficiencies of 99.98 percent at the designated micron rating. With more square feet of media, this cartridge has a higher dirt-holding capacity and will last longer than any other cartridge available. It features standard lengths to fit most housings.